Russia's former defence minister Anatoly Serdyukov has kept silent after being summoned for questioning in a high-profile corruption investigation.
Mr Serdyukov was supposed to speak as a witness, but refused because his lawyer was ill, Russian news agencies report.
The FBI-style Investigative Committee (SK) is probing alleged fraud involving at least $100m (£60m) at a state-run military contractor, Oboronservice.
Mr Serdyukov was dismissed by President Vladimir Putin last month.
He has reportedly been summoned for questioning again on 11 January.
"The minister said straight away that his lawyer Genrikh Padva was sick, and so he was unable to give evidence in his absence and asked to have the questioning rescheduled," the SK's spokesman Vladimir Markin told Interfax news agency.
Mr Serdyukov "is prepared to co-operate with the investigators", Mr Markin added.
Mr Serdyukov was replaced as defence minister by Sergei Shoigu, formerly emergencies minister and a loyal ally of President Putin.
Days later, Mr Putin also dismissed the armed forces chief of general staff, Gen Nikolai Makarov.
Russian authorities are investigating the sale of defence ministry assets at prices below market value.
Oboronservice is suspected of having sold assets to commercial firms at a loss of nearly $95m. Its activities include servicing military aircraft and arms and constructing military facilities.
Several Oboronservice employees have been arrested and five cases of suspected fraud have been launched by the SK. Mr Serdyukov's top aides have also been replaced.
Two suspects are under arrest - Yekaterina Smetanova, who chose buyers for defence ministry property, and her husband Maxim Zakutailo, who ran a military equipment depot.
One of Mr Serdyukov's former subordinates at the ministry, Yevgenia Vasilyeva, is under house arrest.